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-rw-r--r--src/mame/video/mario.c157
1 files changed, 157 insertions, 0 deletions
diff --git a/src/mame/video/mario.c b/src/mame/video/mario.c
new file mode 100644
index 00000000000..ac9ac5bbb3a
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+++ b/src/mame/video/mario.c
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+/***************************************************************************
+
+ video.c
+
+ Functions to emulate the video hardware of the machine.
+
+***************************************************************************/
+
+#include "driver.h"
+
+static UINT8 gfx_bank, palette_bank;
+
+static tilemap *bg_tilemap;
+
+/***************************************************************************
+
+ Convert the color PROMs into a more useable format.
+
+ Mario Bros. has a 512x8 palette PROM; interstingly, bytes 0-255 contain an
+ inverted palette, as other Nintendo games like Donkey Kong, while bytes
+ 256-511 contain a non inverted palette. This was probably done to allow
+ connection to both the special Nintendo and a standard monitor.
+ The palette PROM is connected to the RGB output this way:
+
+ bit 7 -- 220 ohm resistor -- inverter -- RED
+ -- 470 ohm resistor -- inverter -- RED
+ -- 1 kohm resistor -- inverter -- RED
+ -- 220 ohm resistor -- inverter -- GREEN
+ -- 470 ohm resistor -- inverter -- GREEN
+ -- 1 kohm resistor -- inverter -- GREEN
+ -- 220 ohm resistor -- inverter -- BLUE
+ bit 0 -- 470 ohm resistor -- inverter -- BLUE
+
+***************************************************************************/
+PALETTE_INIT( mario )
+{
+ int i;
+ #define TOTAL_COLORS(gfxn) (machine->gfx[gfxn]->total_colors * machine->gfx[gfxn]->color_granularity)
+ #define COLOR(gfxn,offs) (colortable[machine->drv->gfxdecodeinfo[gfxn].color_codes_start + offs])
+
+
+ for (i = 0;i < machine->drv->total_colors;i++)
+ {
+ int bit0,bit1,bit2,r,g,b;
+
+
+ /* red component */
+ bit0 = (*color_prom >> 5) & 1;
+ bit1 = (*color_prom >> 6) & 1;
+ bit2 = (*color_prom >> 7) & 1;
+ r = 255 - (0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2);
+ /* green component */
+ bit0 = (*color_prom >> 2) & 1;
+ bit1 = (*color_prom >> 3) & 1;
+ bit2 = (*color_prom >> 4) & 1;
+ g = 255 - (0x21 * bit0 + 0x47 * bit1 + 0x97 * bit2);
+ /* blue component */
+ bit0 = (*color_prom >> 0) & 1;
+ bit1 = (*color_prom >> 1) & 1;
+ b = 255 - (0x55 * bit0 + 0xaa * bit1);
+
+ palette_set_color(machine,i,MAKE_RGB(r,g,b));
+ color_prom++;
+ }
+
+ /* characters use the same palette as sprites, however characters */
+ /* use only colors 64-127 and 192-255. */
+ for (i = 0;i < 8;i++)
+ {
+ COLOR(0,4*i) = 8*i + 64;
+ COLOR(0,4*i+1) = 8*i+1 + 64;
+ COLOR(0,4*i+2) = 8*i+2 + 64;
+ COLOR(0,4*i+3) = 8*i+3 + 64;
+ }
+ for (i = 0;i < 8;i++)
+ {
+ COLOR(0,4*i+8*4) = 8*i + 192;
+ COLOR(0,4*i+8*4+1) = 8*i+1 + 192;
+ COLOR(0,4*i+8*4+2) = 8*i+2 + 192;
+ COLOR(0,4*i+8*4+3) = 8*i+3 + 192;
+ }
+
+ /* sprites */
+ for (i = 0;i < TOTAL_COLORS(1);i++)
+ COLOR(1,i) = i;
+}
+
+WRITE8_HANDLER( mario_videoram_w )
+{
+ videoram[offset] = data;
+ tilemap_mark_tile_dirty(bg_tilemap, offset);
+}
+
+WRITE8_HANDLER( mario_gfxbank_w )
+{
+ if (gfx_bank != (data & 0x01))
+ {
+ gfx_bank = data & 0x01;
+ tilemap_mark_all_tiles_dirty(ALL_TILEMAPS);
+ }
+}
+
+WRITE8_HANDLER( mario_palettebank_w )
+{
+ if (palette_bank != (data & 0x01))
+ {
+ palette_bank = data & 0x01;
+ tilemap_mark_all_tiles_dirty(ALL_TILEMAPS);
+ }
+}
+
+WRITE8_HANDLER( mario_scroll_w )
+{
+ tilemap_set_scrolly(bg_tilemap, 0, data + 17);
+}
+
+static TILE_GET_INFO( get_bg_tile_info )
+{
+ int code = videoram[tile_index] + 256 * gfx_bank;
+ int color = (videoram[tile_index] >> 5) + 8 * palette_bank;
+
+ SET_TILE_INFO(0, code, color, 0);
+}
+
+VIDEO_START( mario )
+{
+ bg_tilemap = tilemap_create(get_bg_tile_info, tilemap_scan_rows,
+ TILEMAP_TYPE_PEN, 8, 8, 32, 32);
+
+ state_save_register_global(gfx_bank);
+ state_save_register_global(palette_bank);
+}
+
+static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect)
+{
+ int offs;
+
+ for (offs = 0;offs < spriteram_size;offs += 4)
+ {
+ if (spriteram[offs])
+ {
+ drawgfx(bitmap,machine->gfx[1],
+ spriteram[offs + 2],
+ (spriteram[offs + 1] & 0x0f) + 16 * palette_bank,
+ spriteram[offs + 1] & 0x80,spriteram[offs + 1] & 0x40,
+ spriteram[offs + 3] - 8,240 - spriteram[offs] + 8,
+ cliprect,TRANSPARENCY_PEN,0);
+ }
+ }
+}
+
+VIDEO_UPDATE( mario )
+{
+ tilemap_draw(bitmap, cliprect, bg_tilemap, 0, 0);
+ draw_sprites(machine, bitmap, cliprect);
+ return 0;
+}